Honestly, there's more ground for obstruction of justice charges against Trudeau for his role in the SNC-Lavalin scandal than anything I've seen for Trump.
None of his crimes are easy to prosecute while he is in office; the distractions won't have much effect once he is not in office. So I doubt that that is exactly the issue.
Sure, but that's purely a political constraint, not a legal one, and he's well aware of that. There doesn't appear to be any will in the democratic or republican leadership to advance motions to remove him from power. Given the lack of any interest in this regard, the constant onslaught of allegations of foreign intervention seems to be more of an effort to shift blame away from the weaknesses of a certain 2016 democratic nominee and hedging against a 2020 loss when certain american billionaires had demonstrably many times the influence of any foreign government. A change in political power could find him out of office very quickly.
There is considerable debate on whether it is legal to criminally prosecute a sitting President, for different reasons applying to state vs. federal charges. At best, it would involve getting courts to resolve novel questions of Constitutional law about which the legal community has no consensus and which there is no direct on-point precedent.
So, no, it's a legal constraint.
> There doesn't appear to be any will in the democratic or republican leadership to advance motions to remove him from power.
The Democratic leadership is fully behind efforts to removw him from power shortly after the next Congress opens. They also aren't standing in the way of efforts to do sooner (impeachment hearings in the House begin in less than a week).
The Republican leadership, sure, fits your description.
You may be right, maybe the courts will rule that certain actions are legal or not. The fact that we're talking about this in the hypothetical is a clear indication of failure of leadership. The party is directionless and floundering. Trump is going to do just fine.
That's how it's always been, throughout recorded history. If you constrain military intelligence too much, as happened in the US between WWI and WWII, and during the 90s, you get fuckups like Pearl Harbor and 9/11.
But on the other hand, if military intelligence (and the military generally) operates too much domestically, then you have (doh) a military government. So it's a delicate balance.
As far as I can tell, the US does not have a military government. However, as we saw from documents released from Snowden's cache, the military does operate too much domestically. It's arguably mainly about terrorism and the drug war. But although there are certainly impacts on civil liberties, especially on some ethnic groups, at least there's apparently not much outright suppression of political and social dissidents. So that's reassuring.
Regarding talent, the CIA and NSA clearly recruit in academia. However, I've read that the NSA also draws heavily on enlisted personnel, and trains them in house. Also, I've read that it recruits from the non-white-hat hacker community. But maybe that's dated information.